Demonstrating their commitment to keep improving the AM4 platform, AMD has just published a suite of details about their upcoming AGESA 1.0.0.6 firmware. Of particular interest here, the latest firmware is going to enhance memory overclocking and compability, as well as add a much needed virtualization-related feature.

AGESA is an acronym for “AMD Generic Encapsulated System Architecture", and it is essentially the foundational code on which BIOS files for AM4 motherboards are built. When the Ryzen AM4 platform was launched back in March, the early AGESA versions lacked a lot of the core capabilities and settings that we have come to expect from a modern platform. As a result, motherboard manufacturers did not have a lot to work with when it came to creating feature-rich custom BIOSes for their own motherboards. Since then AMD has been pretty vocal and proactive about fixing any bugs, opening up new BIOS features, and improving overclocking.

With this new AGESA version, AMD has added 26 new memory-related parameters. The most dramatic improvement is the significant expansion of memory speed options. If we exclude base block overclocking - which relatively few motherboards support - the AM4 platform has thus far been effectively limited to memory speeds of DDR4-3200. Not only that, but the supported range of options from DDR4-1866 to DDR4-3200 was in large 266MT/s increments. With AGESA 1.0.0.6, memory frequencies have not only been expanded all the way up to DDR4-4000, but between DDR4-2667 and DDR4-4000 the increments have been reduced to 133MT/s. Not only does this mean that more memory kits will be able to be run at their rated speed - and not get kicked down to the nearest supported speed - but it also significantly reduces the high-speed memory gap that the AM4 platform had with Intel's mainstream LGA1151 platform.

The other important announcement is the unlocking of about two dozen memory timings. Up until now, only five primary memory timings have been adjustable and there wasn't even a command rate option, which was natively locked to the most aggressive 1T setting. All of this should help improve overclocking and most importantly compatibility with the large swathe of DDR4 memory kits that have largely been engineered with Intel platforms in mind.

The last addition should excite those interested in virtualization. AMD has announced "fresh support" for PCI Express Access Control Services (ACS), which enables the ability to manually assign PCIe graphics cards within IOMMU groups. This should be a breath of fresh air to those who have previously tried to dedicate a GPU to a virtual machine on a Ryzen system, since it is a task that has thus far been fraught with difficulties.

AMD has already distributed the AGESA 1.0.0.6 to its motherboard partners, so BIOS updates should be available starting in mid to late June. Having said that, there are apparently beta versions currently available for the ASUS Crosshair VI and GIGABYTE GA-AX370-Gaming 5.

Unfortunately their infinity fabric runs at the memory speed, which means inter-module communication is directly affected by the memory speed. This will be an issue for servers where you can only get DDR4-2333 with ECC. 32 cores with very slow inter communication.Reply

well... yes and no.The attractive thing about AMDs design in servers is that you have the same internal latency no matter how many cores you throw at the design. So for small core count designs Intel is going to eat AMD's lunch. But for high core counts AMD systems will hum along nicely, while Intel chips will get slower and slower.Reply

@any from Anandtech: would y'all consider revisiting Ryzen and Core performance in the context of higher frequency (say, 3200) MHz memory? I don't know if I've ever seen a piece from y'all about this, and I'd love to get one from a high quality source on precisely how much each uArch enjoys the extra memory speed.Reply

What about memory density issues? Previously, at max capacity i.e. dual rank, 4 dimms, or the usual 64GB config, the stock supported speed was 1833, though I think some bios can allow manual overclocking to 2133

I hope with the change to 2T command rate, that will allow higher speeds. It would be nice to support 64GB at JEDEC 2400.Reply

"even a command rate option, which was natively locked to the most aggressive 1T setting"

Not quite true. While the Command Rate option could not be changed by the user, it did change, automatically, based on multiplier. Example (AsRock 1.5x-1.9x BIOS versions): at 2400, 2T was used, while at 2667, 1T was used. It's possible this changed by OEM.Reply